Discussed in other comments... but the zero-with-slash is only used in the flight plan section of that display; all of the other zeros are without the slash. It

Discussed in other comments... but the zero-with-slash is only used in the flight plan section of that display; all of the other zeros are without the slash. It seems they only use the zero-with-slash where there might be a risk of ambiguity between 0 and O... everywhere else where it's just numeric readouts, there's no slash because there's no risk of confusion, and I'm guessing they decided zero-with-slash is more visually ugly/less intuitive for quickly reading numbers than zero-without-slash.